Process for producing finely divided sulfur



Oct. 21, 1952 D. c. RAILSBACK PROCESS FOR PRODUCING FINELY DIVIDED SULFQR Filed July 11. 1949 & mm

mmP mI INV EN TOR. D. C. RAILSBACK A TTORNE Y5 portions. divided solvent are solidified into finely divided Patented Oct. 21, 1952 Darrell C. Railsbaclr, Phillips, Tex assignor to Phillips Petroleum Company, a corporation of Delaware Application July 11, 1949, Serial No. 104,024

. 13' Claims.

1 This invention relates to a method ofproces sing sulphur. In one of its more specific. aspects it relates to a method of producing finely divided :sulphur. In another of its more specific aspects it relates to a method of producing finely divided sulphur from an emulsion.

Sulphur has long been used in various manufacturing and industrial processes.- In many in? dustries it isquite desirable to utilize the sulphur inta finely divided form. Conventional processes which have been devised for the productionof finelydivided sulphur are relatively expensive. An example of one of the conventionalexpensive methods of producing finely divided sulphur is the production of flowers of sulphur which is a batch process. It is well known that batch op.- eration is more expensive than continuous processes. Finely divided sulphur is also produced by grinding ormilling solidified masses ofsulphur. Thatv type of 1 operation requires expensive machinery and considerable power consumption.

Broadly speaking, this invention comprises the 'emulsification of a hot, Water immiscible hydrocarbon solution of sulphur in watertso as to divide the dissolved sulphurinto smallseparated The sulphur in the: small portions of particles. The water and hydrocarbon are then removed from :around the finely divided. sulphur material. Production of finely divided 'sul- .phur in this .manner may be carried on. very economically as compared to conventional methods of producing finely divided sulphur.

An object. of .this invention is to" provide a method for producing. finely. divided. sulphur. Another object of this invention .is to produce finely divided sulphur fromJanx emulsion stage. Another object: of this inventionis to provide .a-low temperature process for the production of finely divided. sulphur. Another object of. this'in-ivention is to provide. a method for producing finely'dividedamorphous sulphur. Another object of the invention. is to produce an economical method for producing sulphur; Other and further objects and advantages will be apparent to one. skilled in theart upon study :of :the .accoms conveyor conduit l2 which. communicateslbetween tank; II and asulphur supply'source, n1ot shown. Aheater i3 is provided adjacent the'low 2 er portion of tank H and provides heat for the purpose of melting the crude sulphur in tank I l.

Thearnolten sulphur is removed from tank H by means of conduit M which has pump l5 positioned therein for the purpose of supplying the necessary motivation to move the molten sulphur from tank H toitank l6. Tank I6 is provided withan agitator I! and with heating coilsl'8. Any conventional hot heat exchange medium .canbe utilized for the purpose of supplying heat totank. I6 through coils 18 in an indirect heat exchange. Conduit l9 communicates between a hydrocarbon supply source, not shown, and tank I6 ,Valve 21 is provided in line I9 so as to control or stop flow therethrough. A hydrocarbon fraction, such asv a petroleum or coal tar hydrocarbon material, is preferably supplied to tank 16 throughconduitl 9 in a heated condition. The temperature of the heated hydrocarbon material is usually about thetemperature of the molten sulphur when the sulphur material which is supplied to tank I6 is in a molten state.

In one modification of the invention, thecrude sulphur from the sulphur supply source, not shown, is supplied in a orushedcondition directly to tank. lfi'through sulphur supply conduit v22. The hydro-carbon .material which is supplied to tank I6-is in this case also preferably maintained in a heatedzcondition.

Sulphur which is supplied to tank. [6 through conduits M or 22 ismixed with the heated'hydrocarbon' material in. tank I6, preferably by means of agitation provided by agitator I! so as to. dissolve the, sulphur material in' the heated hydrocarbon. Thezsulphur-containinghydrocar bonmaterial within tank [=6 is maintained in a liquid condition at a temperature above the melting. pointvof sulphur, preferablyat a ter'n perature of at least 240? F. while maiiitainirrgthe agitator -25 so as to form a hydrocarbon-in water emulsion. In such: an emulsion the water'materialforms an outer phaseabout an :inner hy'-- drocarbonphase,v which inner phasevnompri'ses thesulphur-containing hydrocarbon ..material.

This emulsification, is a highlyi'mport'ant feature amine hydrochloride, rosin soaps, or sulfonates,

through conduit 30. The solubility of the sulphur in hydrocarbon is increased by the addition of between and volume per cent ditertiary" disulfides ranging from C4S to ClGS to the mixture. The disulfides may be added to tank I6 throughline I9. Fine dispersion of the sulphurcontaining hydrocarbon material in; water great- 1y reduces the possibility for the growth of large sulphur crystals upon cooling of the'sulphurcontaining hydrocarbon.

In one concept of the invention, the emulsion 4 depend upon the boiling point of the hydrocarbon material being used as the solvent in'the system. If a portion of the hydrocarbon material boils above the boiling point of water, the hydrocarbon phase will be removed first in dropout chamber 42. In such a case, the hydrocarbon material will be removed from dropout chamber 42 through conduit 44, pump 45, and valve 46. In case the water-rich phase is removed first in dropout chamber 42, valve 46 is closed and the water-rich stream is passed through conduit 44,

pump 45, and valve 41 into tank 24. Any excess waterv or water-rich phase material is removed through conduit 48 and valve 49. The entire water-richphase can be discarded if desired.

""The' above described process is'in some instances modified by maintaining the vaporizer of hydrocarbon material in water is passed through conduit 21 and valve 28 through cooler 29 positioned therein so as to cool the emulsion to a temperature below. the solidification point of the sulphur. In this manner, the sulphur is solidified as finely divided particles within the hydrocarbon in water emulsion. The solubility of sulphur in the cold hydrocarbon material is much-less than in the heated hydrocarbon. The

solid sulphur is thus not materially dissolved by the hydrocarbon in the cooled emulsion. The amount" of sulphur which is contained within each droplet of hydrocarbon material, whichzis in. turn encompassed by an outer phase of water, is very'small. The resulting solid sulphur particles which are formed during the cooling are thusquite small. The cooled emulsion, at a temperature below about 230 F., is passed from cooler 29 by means of conduit 3! through pump 32 positioned therein, through an injector 33, and into vaporizer 34 wherein the solid sulphur particles are separated from the hydrocarbon water emulsion by the flow of partial pressure gas, such as air or steam, which is injected at inlet. 35in the lower portion of vaporizer 34 and passes upwardlythrough the vaporizer. Separation of the vaporous material from the finely divided solid, sulphur material is ordinarily better accomplished when'theemulsion which is passed through pump 32 is placed under a pressure of at least 100 p. s. i. and preferably under a pressure of at least 150 p. s. i. Bafile members 35 are provided in theupper portion of vaporizer 34 and bafile the flow of gaseous materials up- Wardly through the vaporizer so as'to aid in the separation of lthe solid sulphur material from the vapors. removed from the lower portion of vaporizer 34 through outlet conduit 3'! and valve member 38. The gaseous materials are removed from the upper portion of vaporizer 34 through outlet conduit 39. andiarepassed through cooler 4| in" .which the temperature of the effluent material is lowered to suchla'point that either the hydrocarbon material or a .water-rich'material'is condensed, depending :upon their condensation points. The cooled: efiluent stream is passed from cooler 4| todropout chamber 42 in which the condensed" material is removed from the gas- -eousmaterial of. the ellluent stream. The remaining gaseous material of the efiluent stream is passed through a second cooler 43'wherein the condensable vapors. are. condensed. The hydrocarbon fraction "stream which is I. separated. as one phase of the condensed effluent material is recycled to tank I6 as a portion. of the hydrocarbon solvent. Whether the hydrocarbon phase or. .the water-rich'phase is r condensed first will The finely divided sulphur'material is under reduced pressure rather than utilizing a partial pressure gas to aid in the separation of finely divided sulphur, water, and hydrocarbon materials.

In case the hydrocarbon phaseis removed first in dropout chamber .42, the water-rich phase may be passed through separator 5|, conduit 52, pump 53, and valve 54 to tank 24. Any excess-water or water-rich phase material'may be removed from the system through conduit 55 and valve 56. Any non-condensable materialis removed from separator 51' through outlet conduit 51. In case the water-rich phase is removed indropout chamber .42, the hydrocarbon phase is recycled to tank l6 through conduit 52,. pump 53,'and valve 58, whilevalve 54 is closed.

In another modification of the invention, the heated sulphur-containing hydrocarbon mate.- rial water emulsion is passed from tank 24 through conduit 21; valve, 59, andconduit 6| so as to bypass cooler 29, valveI28 being closed. Thematerial is placed under pressure as above described by pump 32 in conduit (Hand is. passed through valve 62, conduit '63; heater 64,. and valve to injector 33, "valveififi being closed. In this modification the heated sulphur-containing material is vmaintainedv at a temperature substantially close to the. evaporation point, of the hydrocarbon. solvent and the water. .When the sulphur-containing material is injected into vaporizer .34, the .hydrocarbon and water are pressure gas isutilized,"-instead vaporizer 34 is .maintained under a partial vacuum. The finely dividedsulphur material is .removed fromthe lower portion of vaporizer 34 through outlet conduit 31 and valve 38. The vaporous materials are removed from the upper portion of vaporizer 34 throughconduit 39. The vapors are passed through valve 61 and conduit 68 into a barometric condenser 69 intermediate its. ends. Water material is suppliedto a pointabovev theinjection of vaporous. materials incond'enser 69 through conduit H. The water material contacts the vaporous materials directly, causing the materials to be condensed, thus reducing the'volume of material within condenser 69'ifand applying the partial vacuumv to vaporizer chamber 34, valve 12 being closed. The condensed materials, together..with the water quench, are removed from the lower portion'of condenser 69 through conduit .13 and. are" passed into a separator; 14 wherein: water and hydrocarbon'phases areseparately formed. Thehydrocarbon phase is with- .drawn fromthe upper portion of separator-.14 through iconduitt 15 and: is;'passed through-valve f Hi into the downstream tions boiling within the above "boiling *rsn'g' invention.

term at low storage temperatures.

expanses F I end- 0f conduit iiiand thus into chamber -'l6,valve 2| b'eing 'clo'sedor fresh hydrocarbon to tank-1B. l -A portion "of the water phase is removed {from separator *14 tlirough conduit Tl l and passed through "valve 78 into the downstream end of conduit '2 6, 51,116. thence'; into chamber 24. A portionof the 'wa'ter phase maybe passed from separator- 14 through conduit 1 9: and pump -81 to condu'it H l for -reinjection "into condenser -69. Any "excess water may "be discarded fr'omseparator "1 4 through conduit'BZ.

"The petroleum fraction'which is' used as the also operate very successfully in the process of' this As the amount of sulphur in ee'ach droplet is reduced as a result of 'thedroplet-size 'of'said'emulsion the opportunity 'for the growth of sulphur crystals is also greatly Te'ducedi The finely divided sulphur which is'ordina-rily formed by the process of this invention in-which the sulphur containing petroleum fraction is heated to a temperature of between 240 Ffian'd 650 inmixer l6 is'the"monoclinic type sulphur which is soluble in carbon disulfide. 'The process of this inventionma'y, however, beutillzed so as to form "finely divided sulphur in "the amorphous state, the amorphous sulphur being insoluble in carbon disulfide. It is nec- 'essary .in'the'forma'tion 30f theamorphous sul- Lphur that the "sulphur and petroleum fraction be heated to a temperature above 660 F., but

preferably not above 800 F. The liquid patroleum fraction must contain su'fiicient sulphur in such a process as tube in a saturated state within'the above high temperature range. When such conditions-are met the sulphur material is shock cooled from a temperature within the latter boiling range and"will'form'solid' arnorphous particles disulfide. I l

Insoluble sulphur tends to v revert to a soluble e I Suchreversion 'isjg'reat1y increased when the sulphur Imawhich are insoluble 'in 'c'arbon terial is contacted with water before itlso'li'difies." By the process of this'invention the sulphur 'is dissolved in the hydrocarbon material and is thus-kept from contact with the water material until after solidification of the sulphur. Reversion of the insolubley form of sulphur to the soluble form is greatly retarded by contacting the sulphur with a halogen or a halogen providing material. The halogens which are The concentration or the psul'p'hur "and droplet size ofthe 'sulphur-conta ining hydrocarbon in the emulsion can be 're'gulated"by means of temperature and degree of agitation" of the sulphur-containing petroleum-fraction in the emulsion. Finely divided emulsion particle size is favored by increasing-the intensity'of agitation intank 24 andto a lesser degree by higher temperature.

'vided sulphur iwhich comprises the steps 'ofdissolving-"su1pl'iur"in a hydrocarbon fraction -in? "a liquid state 'at a temperature of at least 240 E; "forming an emulsion -.'of"-said' sulphur-containing v s i jvfded-sulphurwith'a halogen selected from the group 'cons'isting'of chlifirir-ie andbromine; and

sion of the insoluble :material.

suitably utilized for the stabilization step are chlorine'sand bromine. f The chlorine'and bromine tend to remove small amounts of water from "the sulphurand in that manner slow the rever- Ordinarily, it is not necessary to utilize over one per cent by weight of a halogen in contact with the sulphur particles :to accomplish the stabilization. :Amor- .phous sulphurgiparticles which are a removed from the vaporizer '34 through conduit 3] may :becontacted 'withha' halogen orl'h-alogen" providing ma- "te'r'i-a in'a Echamber, not-"shown, :for the purpose of stabilizing the amorphous sulphur" particles.

other and' iurther"modifications of this inventiomwillbeapparent to those skilledin the art -upon study""of this disclosure. Such :modificationsareiloelieved to be within the spirit and-the scope of theidisclosure .or this invention;

I-claim:--f

1 A J process "for the :production of finely dihydrocarb'on :fractionin water; placinggsai-d -emuls'i'on under pressure; injecting 'said 'ernul- .si'on into I-a. vaporization zone under vaporizing conditions,"awherebv-said hydrocarbon and water are vaporized, a separatesulphur "particle is 'gformed from-each individual droplet of said -.emulsion as the result-of said vvaporization and said hydrocarbon andwater vapors are separated from r-esul-tins finely divided solid sulphur; and

recovering said finely divided sulphur.

2, The process of claim 1;, wherein an emulsion --accelerator selected l'from the group consisting of dodecylamine hydrochloride," rosin soaps, and

suifonates is'mixed withlsai'dfhydrocarbon frac- 1 tionandsaid sulphur in an amount 'upto 2 volume per centrb-ased uponsaid hydrocarbon.

3, The process of claim 1, wherein ditertiary -disulfides within the range of from C4 to 015' are mixed with said;hydrocarbon fraction land said vsulphur in an amount of between 15 and 35 'vol- ;;ume percent based upon said hydrocarbon.

4. A process for the production of fine1y"di- --vided sulphur which comp-rises the steps of dissolving sulphur-in aliquid hydrocarbon fraction in a mixing zone atatemperature of between 660" F. "and 800-F :forming an emulsion of said sulphur-containing hydrocarbon in water at ,a temperature of between 660 F. and 800 .F.;

flashing saidemulsioni-nto a vaporization zone under vaporizing conditions, whereby said hydrocarbon-"and water are vaporized, said sulphur is solidified as finely "divided particles'irom in- -'-div-idual drop1ets of said emulsion as the result fof said' vaporization, and said hydrocarbon and water 'va'pors are separated from resulting finely divided solid "lilp'hur; contacting the ,finely direcovering said finely divided sulphur.

5. Aprfocessior the production of 'ii'nely divided sulphur which'comprises the steps of dissolving sulphur in a liquid hydrocarbon fraction in a"niixirig zone-at a't'emperature of at least "240" IFL; forming'an emulsion of said sulphurcontaining H hydrocarbon fraction in water; in- J'e'cting :sai'demuls'ion "into a vapo'rizati-on'zone under vaporizing conditions was to'vaporize said "hydrocarbon and'water, solidify finely divided sulphur as the result of said vaporization and to separate said finely divided solid sulphur from said water and hydrocarbon vapors; remov- :ing and recovering .saidzifinely divided solid sulsphur -material from the bottomportion of said xvaporization zoneyremoving efliuent material fromthe upper portionv of said vaporization zone; .separating;,Ehydrocarboh: materials: from said ef- "fluent materials; and recycling said hydrocarbons as a liquid fraction to said mixing zone.

: :6. SA process for. theproduction of finely divided wsulphur; which :comprises. the steps of dissolving molten sulphur in'a: liquid-hydrocarbon fraction. a which ,rboils, inatherrange "of? between 90 F. 1 and 390: F., in .a' mixingzone at;:-a'-:temp,erature between 240 Rand-800? F.; forming an-emulsion of said sulphur-containing hydrocarbon in water;

; cooling said emulsion was to solidify said sulphur in :saidp; emulsion. as finely divided particles; in- ,Jecting .said-emulsiontinto -a vaporization zone and into the presence of astream'of partial pressure gas under vaporizing conditions so as to vaporize said hydrocarbon: and'water, and separate said-finely divided solid sulphur-, from said Water. and hydrocarbon vapors removing said finelyndivided solid sulphur material from the bottom 'portionoffisaid vaporization zone; removingefiluent material from the upper portion of said vaporization zone; separating hydrocarbon materials from said 1 'effluent material; and recycling said hydrocarbons as a liquid fraction to s'aidmixing zone."- i "7. A'proce's's for the production of finely'divided sulphur'which comprises'the steps of dissolving F'crushed sulphur "a liquid hydrocarbon fraction, which boils in'the', range of between 90 F. and 390 F. ,in a mixing zone at a temperature between24 f F; and 800 F.; forming an emulsion not said sulphur-containing hydrocarbon in water; lfiashing said emulsion into a vaporization zone under vaporizing condtions, whereby said hydrocarbonandwater are vaporized and said sulphur is solidified as finely divided particles "from individual droplets of said emulsion as the result of said vaporization; removing said'finely divided 'solid'sul'phur material from the upper portion of said vaporization zone; removing e'fliuent material from the upper portion of said vaporization zone; separating hydrocarbonmaterials from said efliuent material; and recycling" said hydrocarbon'sas a liquid fraction't'o said mixing zone. 1 p i 8. A process for the'production of 'finely'divide'd sulphur which comprises'the steps of dissolving sul'phiirdn a liquid hydrocarbon 'fraction'in a mixing zone at a temperature of between 660 F. and 800F. so as to saturate said hydrocarbon;

agitating said sulphur-saturated. hydrocarbon with liquid water'at a temperature between 660 F. and"800 F. in anemulsification zone'so as to fo'rm a fine hydrocarbon in water emulsion; in-

jecting said emulsion into a; vaporization zone under vaporizingconditions; whereby-said water and hydrocarbon materials; are vaporized and said sulphur is-shock cooledas the "result of said-vaporization .so-asto solidiiysaid sulphur as finely divided particles from-individual droplets. of said emulsion; removingsaid finely divided solid sulphur material from thelowerportion of said vaporization zone; removing efiluent material sulphur ;'which} comprises the, steps of heating to a molten state heating. hydrocarbon of said sulphur while maintaining said hydrocarbon material in a liquid state; mixingsaidm sulphur. and said heated liguid hydrocarhonqsp emulsion under a pressure of a't least :109

s-finely divided sulphur fromsaidwaterand.hy- ..dr0carbon materials; remo'ving-said-finely divided solid sulphur material from the; bottom portion of said vaporization zone; separatinghyd209.31

The process of claim 9, wherein-;the,. m

q-fractionwhich boils withinathe -range between F. and 300 F.-to atleastthe-melting point injecting said emulsion into avaporization under reduced pressure so as to separa bon material from said efiluent material; andrea liquid fraction to said mixing zone.} a

cycling said separated hydrocarbon material'as 10. The process of vclaim 9; wherein' rich phase is formed from said eflluent materials flWhiCh remain after the separation of-hydrocar- -bon materials therefrom; and. recycling; said water-rich phase to said emulsifyingzonef w terials in said sulphurehydrocarbon mixture lare heated to a temperature between 240 F, and 650, F.

12. The process of claim 9, wherein thefiina- ..terials in said sulphur-hydrocarbon-mixtureare heated to a temperature between 660?. =;F .f 'and 13. A process for the productionoifinely idivided sulphur-which comprises .tl esteps oiheating sulphur to a molten state{ heating ntromatic-rich hydrocarbon I fraction which. ..boils within the range of between 100 F. and 3 007,1 3.

. carbon in Water emulsion; cooling said emulsion so as to solidify said sulphur as finelyldivided particles; placing said emulsion under. a pressure of at least pJs. i flashing said emulsioninto a vaporization zone under reduced-pressure so as to separate said finely divided-sulphur from said water and hydrocarbon materials; removing ...said finely divided solid sulphur. fnaterial' 'from ,the bottom portion of said vaporization zonefa rid ,ti'on of said vaporization zone;

removing eflluent material from'the upper por- DARRELL c. RA ILSBAC KQ;

REFERENCES cir a/TI The following references are vof record in he v file of this patent: a

UNITED STATES Parents 

1. A PROCESS FOR THE PRODUCTION OF FINELY DIVIDED SULPHUR WHICH COMPRISES THE STEPS OF DISSOLVING SULPHUR IN A HYDROCARBON FRACTION IN A LIQUID STATE AT A TEMPERATE OF AT LEAST 240* F.; FORMING AN EMULSION OF SAID SULPHUR-CONTAINING HYDROCARBON FRACTION IN WATER; PLACING SAID EMULSION UNDER PRESSURE; INJECTING SAID EMULSION INTO A VAPORIZATION ZONE UNDER VAPORIZING CONDITIONS, WHEREBY SAID HYDROCARBON AND WATER ARE VAPORIZED, A SEPARATED SULPHUR PARTICLE IS FORMED FROM EACH INDIVIDUAL DROPLET OF SAID EMULSION AS THE RESULT OF SAID VAPORIZATION AND SAID HYDROCARBON AND WATER VAPORS ARE SEPARATED FROM RESULTING FINELY DIVIDED SOLID SULPHUR AND RECOVERING SAID FINELY DIVIDED SULPHUR. 